Alert archive / Virginia / Special Weather Statements in 2011

Special Weather Statement, NWS Blacksburg, VA

May 17, 2011Roanoke County, City of Roanoke, City of Salem, Virginia

NWS Blacksburg, VA issued this special weather statement at May 17, 2011, 2:07 AM EDT for Roanoke County, City of Roanoke, City of Salem, Virginia. It was in force for 53 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 17, 2011, 2:07 AM EDT (06:07 UTC)
Expired: May 17, 2011, 3:00 AM EDT
In force: 53 min
Issued by: NWS Blacksburg, VA

Counties City of Roanoke, VA, City of Salem, VA, Roanoke County, VA

The radar

The Roanoke radar (KFCX), 43 km from the middle of the area, began a volume at 06:09 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Roanoke, VA (KRNK), launched 00:00Z, 6.1 hours before the alert went out and 39 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1175 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -8 m²/s²
0-3 km storm-relative helicity: 118 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

250 
WWUS81 KRNK 170607
SPSRNK

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BLACKSBURG VA
207 AM EDT TUE MAY 17 2011

VAZ018-022-023-034-170700-
BEDFORD VA-BOTETOURT VA-CRAIG VA-ROANOKE VA-
207 AM EDT TUE MAY 17 2011

...A STRONG THUNDERSTORM WILL AFFECT BEDFORD...BOTETOURT...CRAIG AND
ROANOKE COUNTIES...

AT 200 AM EDT...A STRONG THUNDERSTORM WAS LOCATED 5 MILES NORTHWEST
OF STEWARTSVILLE...MOVING NORTHWEST AT 20 MPH.

WIND GUSTS TO 30 MPH AND PEA-SIZED HAIL ARE POSSIBLE WITH THIS STORM.
VERY HEAVY RAIN WILL FALL FROM THIS STORM...AND WILL CAUSE WATER TO
POND ON ROADS AND QUICKLY FILL ROADSIDE DITCHES AND SMALL STREAMS. 

IN ADDITION...THERE IS THE POSSIBILITY OF NEW STORMS DEVELOPING AND 
PASSING OVER AREAS WHICH JUST RECEIVED HEAVY RAIN. THIS MAY CAUSE 
LOCAL STREAMS AND DRAINAGE DITCHES TO FILL UP RAPIDLY...AND POSSIBLY 
OVERFLOW THEIR BANKS. 

THIS STORM WILL BE NEAR CLOVERDALE...ROANOKE...TROUTVILLE...AND NACE
AROUND 210 AM...HOLLINS...AND DALEVILLE AROUND 215 AM...ROANOKE
AIRPORT AROUND 220 AM...SALEM CITY AROUND 225 AM...CATAWBA AROUND 245
AM AND ABBOTT AROUND 250 AM.

LAT...LON 3736 7969 3721 7977 3724 7979 3721 7981
      3723 7982 3721 7984 3723 7985 3722 7986
      3731 8026 3734 8026 3735 8028 3759 8016

$$

16

The office that day

Everything else NWS Blacksburg, VA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 16, 9:48 PM EDT	Flash Flood Warning	RNK	Patrick	6 hr
May 16, 11:22 PM EDT	Special Weather Statement	RNK	Henry, City of Martinsville	53 min
May 17, 12:49 AM EDT	Special Weather Statement	RNK	City of Roanoke	56 min
May 17, 12:53 AM EDT	Special Weather Statement	RNK	Franklin	67 min
May 17, 4:03 AM EDT	Flash Flood Watch	RNK	Alleghany, Amherst, Bath, Bedford, Botetourt, Campbell and 19 more	24 hr
May 17, 11:03 AM EDT	Special Weather Statement	RNK	Floyd, Franklin	57 min
May 17, 1:20 PM EDT	Special Weather Statement	RNK	City of Roanoke, City of Salem	40 min
May 17, 2:24 PM EDT	Special Weather Statement	RNK	Charlotte	51 min
May 17, 3:51 PM EDT	Special Weather Statement	RNK	Patrick	24 min
May 17, 4:55 PM EDT	Special Weather Statement	RNK	Alleghany, City of Covington	50 min
May 17, 5:53 PM EDT	Special Weather Statement	RNK	Greenbrier	52 min

Nearby

Special Weather Statements in Virginia, 2011 Every special weather statement in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.